Kinetics of in vitro renin and angiotensin converting enzyme inhibition by chicken skin protein hydrolysates and their blood pressure lowering effects in spontaneously hypertensive rats

•Short-chain chicken skin peptides had better ACE inhibition than long-chain peptides.•Kinetics of ACE and renin inhibition showed mainly mixed-type mechanism.•The hydrolysates had the strongest blood pressure-lowering effect in spontaneously hypertensive rats.•Blood pressure-lowering effect contrasted with observed in vitro ACE inhibition.•In vitro renin inhibition was consistent with blood pressure-lowering effect. Chicken skin protein hydrolysates (CSPHs) and their membrane ultrafiltration fractions were investigated for their blood pressure lowering effects. Chicken skins from thigh or breast muscles were hydrolyzed with 3% Alcalase or 1% pepsin/pancreatin, respectively; hydrolysates were then fractionated into